* GPL HEADER END
*/
/*
- * Copyright (c) 2013, Intel Corporation.
+ * Copyright (c) 2014, Intel Corporation.
*/
/*
* lustre/osp/osp_trans.c
*
+ *
+ * 1. OSP (Object Storage Proxy) transaction methods
+ *
+ * Implement OSP layer transaction related interfaces for the dt_device API
+ * dt_device_operations.
+ *
+ *
+ * 2. Handle asynchronous idempotent operations
+ *
+ * The OSP uses OUT (Object Unified Target) RPC to talk with other server
+ * (MDT or OST) for kinds of operations, such as create, unlink, insert,
+ * delete, lookup, set_(x)attr, get_(x)attr, and etc. To reduce the number
+ * of RPCs, we allow multiple operations to be packaged together in single
+ * OUT RPC.
+ *
+ * For the asynchronous idempotent operations, such as get_(x)attr, related
+ * RPCs will be inserted into a osp_device based shared asynchronous request
+ * queue - osp_device::opd_async_requests. When the queue is full, all the
+ * requests in the queue will be packaged into a single OUT RPC and given to
+ * the ptlrpcd daemon (for sending), then the queue is purged and other new
+ * requests can be inserted into it.
+ *
+ * When the asynchronous idempotent operation inserts the request into the
+ * shared queue, it will register an interpreter. When the packaged OUT RPC
+ * is replied (or failed to be sent out), all the registered interpreters
+ * will be called one by one to handle each own result.
+ *
+ *
* Author: Di Wang <di.wang@intel.com>
* Author: Fan, Yong <fan.yong@intel.com>
*/
struct osp_async_update_args {
struct dt_update_request *oaua_update;
- unsigned int oaua_fc:1;
+ bool oaua_flow_control;
};
-struct osp_async_update_item {
- struct list_head oaui_list;
- struct osp_object *oaui_obj;
- void *oaui_data;
- osp_async_update_interpterer_t oaui_interpterer;
+struct osp_async_request {
+ /* list in the dt_update_request::dur_cb_items */
+ struct list_head oar_list;
+
+ /* The target of the async update request. */
+ struct osp_object *oar_obj;
+
+ /* The data used by oar_interpreter. */
+ void *oar_data;
+
+ /* The interpreter function called after the async request handled. */
+ osp_async_request_interpreter_t oar_interpreter;
};
-static struct osp_async_update_item *
-osp_async_update_item_init(struct osp_object *obj, void *data,
- osp_async_update_interpterer_t interpterer)
+/**
+ * Allocate an asynchronous request and initialize it with the given parameters.
+ *
+ * \param[in] obj pointer to the operation target
+ * \param[in] data pointer to the data used by the interpreter
+ * \param[in] interpreter pointer to the interpreter function
+ *
+ * \retval pointer to the asychronous request
+ * \retval NULL if the allocation failed
+ */
+static struct osp_async_request *
+osp_async_request_init(struct osp_object *obj, void *data,
+ osp_async_request_interpreter_t interpreter)
{
- struct osp_async_update_item *oaui;
+ struct osp_async_request *oar;
- OBD_ALLOC_PTR(oaui);
- if (oaui == NULL)
+ OBD_ALLOC_PTR(oar);
+ if (oar == NULL)
return NULL;
lu_object_get(osp2lu_obj(obj));
- INIT_LIST_HEAD(&oaui->oaui_list);
- oaui->oaui_obj = obj;
- oaui->oaui_data = data;
- oaui->oaui_interpterer = interpterer;
+ INIT_LIST_HEAD(&oar->oar_list);
+ oar->oar_obj = obj;
+ oar->oar_data = data;
+ oar->oar_interpreter = interpreter;
- return oaui;
+ return oar;
}
-static void osp_async_update_item_fini(const struct lu_env *env,
- struct osp_async_update_item *oaui)
+/**
+ * Destroy the asychronous request.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] oar pointer to asychronous request
+ */
+static void osp_async_request_fini(const struct lu_env *env,
+ struct osp_async_request *oar)
{
- LASSERT(list_empty(&oaui->oaui_list));
+ LASSERT(list_empty(&oar->oar_list));
- lu_object_put(env, osp2lu_obj(oaui->oaui_obj));
- OBD_FREE_PTR(oaui);
+ lu_object_put(env, osp2lu_obj(oar->oar_obj));
+ OBD_FREE_PTR(oar);
}
+/**
+ * Interpret the packaged OUT RPC results.
+ *
+ * For every packaged sub-request, call its registered interpreter function.
+ * Then destroy the sub-request.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] req pointer to the RPC
+ * \param[in] arg pointer to data used by the interpreter
+ * \param[in] rc the RPC return value
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
static int osp_async_update_interpret(const struct lu_env *env,
struct ptlrpc_request *req,
void *arg, int rc)
struct object_update_reply *reply = NULL;
struct osp_async_update_args *oaua = arg;
struct dt_update_request *dt_update = oaua->oaua_update;
- struct osp_async_update_item *oaui;
- struct osp_async_update_item *next;
- struct osp_device *osp = dt2osp_dev(dt_update->dur_dt);
+ struct osp_async_request *oar;
+ struct osp_async_request *next;
int count = 0;
int index = 0;
int rc1 = 0;
- if (oaua->oaua_fc)
- up(&osp->opd_async_fc_sem);
+ if (oaua->oaua_flow_control)
+ obd_put_request_slot(
+ &dt2osp_dev(dt_update->dur_dt)->opd_obd->u.cli);
- if (rc == 0 || req->rq_repmsg != NULL) {
+ /* Unpack the results from the reply message. */
+ if (req->rq_repmsg != NULL) {
reply = req_capsule_server_sized_get(&req->rq_pill,
&RMF_OUT_UPDATE_REPLY,
OUT_UPDATE_REPLY_SIZE);
rc1 = rc;
}
- list_for_each_entry_safe(oaui, next, &dt_update->dur_cb_items,
- oaui_list) {
- list_del_init(&oaui->oaui_list);
+ list_for_each_entry_safe(oar, next, &dt_update->dur_cb_items,
+ oar_list) {
+ list_del_init(&oar->oar_list);
+
+ /* The peer may only have handled some requests (indicated
+ * by the 'count') in the packaged OUT RPC, we can only get
+ * results for the handled part. */
if (index < count && reply->ourp_lens[index] > 0) {
struct object_update_result *result;
rc1 = -EINVAL;
}
- oaui->oaui_interpterer(env, reply, req, oaui->oaui_obj,
- oaui->oaui_data, index, rc1);
- osp_async_update_item_fini(env, oaui);
+ oar->oar_interpreter(env, reply, req, oar->oar_obj,
+ oar->oar_data, index, rc1);
+ osp_async_request_fini(env, oar);
index++;
}
return 0;
}
-int osp_unplug_async_update(const struct lu_env *env,
- struct osp_device *osp,
- struct dt_update_request *update)
+/**
+ * Pack all the requests in the shared asynchronous idempotent request queue
+ * into a single OUT RPC that will be given to the background ptlrpcd daemon.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] osp pointer to the OSP device
+ * \param[in] update pointer to the shared queue
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
+int osp_unplug_async_request(const struct lu_env *env,
+ struct osp_device *osp,
+ struct dt_update_request *update)
{
struct osp_async_update_args *args;
struct ptlrpc_request *req = NULL;
rc = out_prep_update_req(env, osp->opd_obd->u.cli.cl_import,
update->dur_req, &req);
if (rc != 0) {
- struct osp_async_update_item *oaui;
- struct osp_async_update_item *next;
-
- list_for_each_entry_safe(oaui, next,
- &update->dur_cb_items, oaui_list) {
- list_del_init(&oaui->oaui_list);
- oaui->oaui_interpterer(env, NULL, NULL, oaui->oaui_obj,
- oaui->oaui_data, 0, rc);
- osp_async_update_item_fini(env, oaui);
+ struct osp_async_request *oar;
+ struct osp_async_request *next;
+
+ list_for_each_entry_safe(oar, next,
+ &update->dur_cb_items, oar_list) {
+ list_del_init(&oar->oar_list);
+ oar->oar_interpreter(env, NULL, NULL, oar->oar_obj,
+ oar->oar_data, 0, rc);
+ osp_async_request_fini(env, oar);
}
out_destroy_update_req(update);
} else {
return rc;
}
-/* with osp::opd_async_requests_mutex held */
-struct dt_update_request *
+/**
+ * Find or create (if NOT exist or purged) the shared asynchronous idempotent
+ * request queue - osp_device::opd_async_requests.
+ *
+ * If the osp_device::opd_async_requests is not NULL, then return it directly;
+ * otherwise create new dt_update_request and attach it to opd_async_requests.
+ *
+ * \param[in] osp pointer to the OSP device
+ *
+ * \retval pointer to the shared queue
+ * \retval negative error number on failure
+ */
+static struct dt_update_request *
osp_find_or_create_async_update_request(struct osp_device *osp)
{
struct dt_update_request *update = osp->opd_async_requests;
return update;
}
-/* with osp::opd_async_requests_mutex held */
-int osp_insert_async_update(const struct lu_env *env,
- struct dt_update_request *update, int op,
- struct osp_object *obj, int count,
- int *lens, const char **bufs, void *data,
- osp_async_update_interpterer_t interpterer)
+/**
+ * Insert an asynchronous idempotent request to the shared request queue that
+ * is attached to the osp_device.
+ *
+ * This function generates a new osp_async_request with the given parameters,
+ * then tries to insert the request into the osp_device-based shared request
+ * queue. If the queue is full, then triggers the packaged OUT RPC to purge
+ * the shared queue firstly, and then re-tries.
+ *
+ * NOTE: must hold the osp::opd_async_requests_mutex to serialize concurrent
+ * osp_insert_async_request call from others.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] op operation type, see 'enum update_type'
+ * \param[in] obj pointer to the operation target
+ * \param[in] count array size of the subsequent @lens and @bufs
+ * \param[in] lens buffer length array for the subsequent @bufs
+ * \param[in] bufs the buffers to compose the request
+ * \param[in] data pointer to the data used by the interpreter
+ * \param[in] interpreter pointer to the interpreter function
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
+int osp_insert_async_request(const struct lu_env *env,
+ int op, struct osp_object *obj, int count,
+ int *lens, const char **bufs, void *data,
+ osp_async_request_interpreter_t interpreter)
{
- struct osp_async_update_item *oaui;
+ struct osp_async_request *oar;
struct osp_device *osp = lu2osp_dev(osp2lu_obj(obj)->lo_dev);
+ struct dt_update_request *update;
int rc = 0;
ENTRY;
- oaui = osp_async_update_item_init(obj, data, interpterer);
- if (oaui == NULL)
+ oar = osp_async_request_init(obj, data, interpreter);
+ if (oar == NULL)
RETURN(-ENOMEM);
+ update = osp_find_or_create_async_update_request(osp);
+ if (IS_ERR(update))
+ GOTO(out, rc = PTR_ERR(update));
+
again:
rc = out_insert_update(env, update, op, lu_object_fid(osp2lu_obj(obj)),
count, lens, bufs);
+ /* The queue is full. */
if (rc == -E2BIG) {
osp->opd_async_requests = NULL;
mutex_unlock(&osp->opd_async_requests_mutex);
- rc = osp_unplug_async_update(env, osp, update);
+ rc = osp_unplug_async_request(env, osp, update);
mutex_lock(&osp->opd_async_requests_mutex);
if (rc != 0)
GOTO(out, rc);
}
if (rc == 0)
- list_add_tail(&oaui->oaui_list, &update->dur_cb_items);
+ list_add_tail(&oar->oar_list, &update->dur_cb_items);
GOTO(out, rc);
out:
if (rc != 0)
- osp_async_update_item_fini(env, oaui);
+ osp_async_request_fini(env, oar);
return rc;
}
/**
- * If the transaction creation goes to OSP, it means the update
- * in this transaction only includes remote UPDATE. It is only
- * used by LFSCK right now.
- **/
+ * The OSP layer dt_device_operations::dt_trans_create() interface
+ * to create a transaction.
+ *
+ * There are two kinds of transactions that will involve OSP:
+ *
+ * 1) If the transaction only contains the updates on remote server
+ * (MDT or OST), such as re-generating the lost OST-object for
+ * LFSCK, then it is a remote transaction. For remote transaction,
+ * the upper layer caller (such as the LFSCK engine) will call the
+ * dt_trans_create() (with the OSP dt_device as the parameter),
+ * then the call will be directed to the osp_trans_create() that
+ * creates the transaction handler and returns it to the caller.
+ *
+ * 2) If the transcation contains both local and remote updates,
+ * such as cross MDTs create under DNE mode, then the upper layer
+ * caller will not trigger osp_trans_create(). Instead, it will
+ * call dt_trans_create() on other dt_device, such as LOD that
+ * will generate the transaction handler. Such handler will be
+ * used by the whole transaction in subsequent sub-operations.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] d pointer to the OSP dt_device
+ *
+ * \retval pointer to the transaction handler
+ * \retval negative error number on failure
+ */
struct thandle *osp_trans_create(const struct lu_env *env, struct dt_device *d)
{
- struct thandle *th = NULL;
- struct thandle_update *tu = NULL;
- int rc = 0;
+ struct thandle *th = NULL;
+ struct thandle_update *tu = NULL;
+ int rc = 0;
OBD_ALLOC_PTR(th);
if (unlikely(th == NULL))
return th;
}
+/**
+ * Trigger the request for remote updates.
+ *
+ * If the transaction is a remote transaction, then related remote updates
+ * will be sent asynchronously; otherwise, the cross MDTs transaction will
+ * be synchronized.
+ *
+ * Please refer to osp_trans_create() for transaction type.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] osp pointer to the OSP device
+ * \param[in] dt_update pointer to the dt_update_request
+ * \param[in] th pointer to the transaction handler
+ * \param[in] flow_control whether need to control the flow
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
static int osp_trans_trigger(const struct lu_env *env, struct osp_device *osp,
struct dt_update_request *dt_update,
- struct thandle *th, bool fc)
+ struct thandle *th, bool flow_control)
{
struct thandle_update *tu = th->th_update;
- int rc = 0;
+ int rc = 0;
LASSERT(tu != NULL);
- /* If the transaction only includes remote update, it should
- * still be asynchronous */
if (is_only_remote_trans(th)) {
struct osp_async_update_args *args;
struct ptlrpc_request *req;
if (rc == 0) {
args = ptlrpc_req_async_args(req);
args->oaua_update = dt_update;
- args->oaua_fc = !!fc;
+ args->oaua_flow_control = flow_control;
req->rq_interpret_reply =
osp_async_update_interpret;
ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1);
out_destroy_update_req(dt_update);
}
} else {
- /* Before we support async update, the cross MDT transaction
- * has to been synchronized */
th->th_sync = 1;
rc = out_remote_sync(env, osp->opd_obd->u.cli.cl_import,
dt_update, NULL);
return rc;
}
+/**
+ * The OSP layer dt_device_operations::dt_trans_start() interface
+ * to start the transaction.
+ *
+ * If the transaction is a remote transaction, then related remote
+ * updates will be triggered in the osp_trans_stop(); otherwise the
+ * transaction contains both local and remote update(s), then when
+ * the OUT RPC will be triggered depends on the operation, and is
+ * indicated by the dt_device::tu_sent_after_local_trans, for example:
+ *
+ * 1) If it is remote create, it will send the remote req after local
+ * transaction. i.e. create the object locally first, then insert the
+ * remote name entry.
+ *
+ * 2) If it is remote unlink, it will send the remote req before the
+ * local transaction, i.e. delete the name entry remotely first, then
+ * destroy the local object.
+ *
+ * Please refer to osp_trans_create() for transaction type.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] dt pointer to the OSP dt_device
+ * \param[in] th pointer to the transaction handler
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
int osp_trans_start(const struct lu_env *env, struct dt_device *dt,
struct thandle *th)
{
- struct thandle_update *tu = th->th_update;
- struct dt_update_request *dt_update;
- int rc = 0;
+ struct thandle_update *tu = th->th_update;
+ struct dt_update_request *dt_update;
+ int rc = 0;
if (tu == NULL)
return rc;
if (dt_update == NULL)
return rc;
- /* Note: some updates needs to send before local transaction,
- * some needs to send after local transaction.
- *
- * If the transaction only includes remote updates, it will
- * send updates to remote MDT in osp_trans_stop.
- *
- * If it is remote create, it will send the remote req after
- * local transaction. i.e. create the object locally first,
- * then insert the name entry.
- *
- * If it is remote unlink, it will send the remote req before
- * the local transaction, i.e. delete the name entry remote
- * first, then destroy the local object. */
if (!is_only_remote_trans(th) && !tu->tu_sent_after_local_trans)
rc = osp_trans_trigger(env, dt2osp_dev(dt), dt_update, th,
false);
return rc;
}
+/**
+ * The OSP layer dt_device_operations::dt_trans_stop() interface
+ * to stop the transaction.
+ *
+ * If the transaction is a remote transaction, or the update handler
+ * is marked as 'tu_sent_after_local_trans', then related remote
+ * updates will be triggered here via osp_trans_trigger().
+ *
+ * For synchronous mode update or any failed update, the request
+ * will be destroyed explicitly when the osp_trans_stop().
+ *
+ * Please refer to osp_trans_create() for transaction type.
+ *
+ * \param[in] env pointer to the thread context
+ * \param[in] dt pointer to the OSP dt_device
+ * \param[in] th pointer to the transaction handler
+ *
+ * \retval 0 for success
+ * \retval negative error number on failure
+ */
int osp_trans_stop(const struct lu_env *env, struct dt_device *dt,
struct thandle *th)
{
struct thandle_update *tu = th->th_update;
struct dt_update_request *dt_update;
- int rc = 0;
+ int rc = 0;
LASSERT(tu != NULL);
- LASSERT(tu != LP_POISON);
+ LASSERT(tu != LP_POISON);
+
/* Check whether there are updates related with this OSP */
dt_update = out_find_update(tu, dt);
if (dt_update == NULL) {
if (is_only_remote_trans(th)) {
if (th->th_result == 0) {
struct osp_device *osp = dt2osp_dev(th->th_dev);
+ struct client_obd *cli = &osp->opd_obd->u.cli;
+
+ rc = obd_get_request_slot(cli);
+ if (!osp->opd_imp_active || osp->opd_got_disconnected) {
+ if (rc == 0)
+ obd_put_request_slot(cli);
- do {
- if (!osp->opd_imp_active ||
- osp->opd_got_disconnected) {
- out_destroy_update_req(dt_update);
- GOTO(put, rc = -ENOTCONN);
- }
+ rc = -ENOTCONN;
+ }
- /* Get the semaphore to guarantee it has
- * free slot, which will be released via
- * osp_async_update_interpret(). */
- rc = down_timeout(&osp->opd_async_fc_sem, HZ);
- } while (rc != 0);
+ if (rc != 0) {
+ out_destroy_update_req(dt_update);
+ goto put;
+ }
rc = osp_trans_trigger(env, dt2osp_dev(dt),
dt_update, th, true);
if (rc != 0)
- up(&osp->opd_async_fc_sem);
+ obd_put_request_slot(cli);
} else {
rc = th->th_result;
out_destroy_update_req(dt_update);
git://git.whamcloud.com / fs / lustre-release.git / blobdiff